-/*******************************************************************************\r
- * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
- * in Industry THTH ry.\r
- * All rights reserved. This program and the accompanying materials\r
- * are made available under the terms of the Eclipse Public License v1.0\r
- * which accompanies this distribution, and is available at\r
- * http://www.eclipse.org/legal/epl-v10.html\r
- *\r
- * Contributors:\r
- * VTT Technical Research Centre of Finland - initial API and implementation\r
- *******************************************************************************/\r
-package org.simantics.db.common.procedure.guarded;\r
-\r
-import java.util.concurrent.atomic.AtomicBoolean;\r
-import java.util.concurrent.atomic.AtomicInteger;\r
-\r
-import org.simantics.db.AsyncReadGraph;\r
-import org.simantics.db.common.procedure.adapter.AsyncProcedureAdapter;\r
-import org.simantics.db.procedure.AsyncProcedure;\r
-import org.simantics.db.procedure.Procedure;\r
-\r
-/**\r
- * An asynchronous database callback procedure that is guarded against multiple\r
- * invocations to {@link Procedure#execute(Object)} and\r
- * {@link Procedure#exception(Throwable)}. Only the first invocation of is\r
- * delegated or the Nth invocation to {@link Procedure#execute(Object)} where\r
- * Nth is <code>expectedResults</code>.\r
- * \r
- * @author Tuukka Lehtonen\r
- * \r
- * @param <T>\r
- */\r
-public class GuardedAsyncProcedureWrapper<T> extends AsyncProcedureAdapter<T> {\r
-\r
- private final AsyncProcedure<T> procedure;\r
- private final AtomicBoolean onceGuard = new AtomicBoolean(false);\r
- private final AtomicInteger resultCounter;\r
-\r
- public GuardedAsyncProcedureWrapper(AsyncProcedure<T> procedure, int expectedResults) {\r
- this.procedure = procedure;\r
- this.resultCounter = new AtomicInteger(expectedResults);\r
- }\r
-\r
- @Override\r
- public void exception(AsyncReadGraph graph, Throwable t) {\r
- if (onceGuard.compareAndSet(false, true)) {\r
- procedure.exception(graph, t);\r
- }\r
- }\r
-\r
- @Override\r
- public void execute(AsyncReadGraph graph, T result) {\r
- int count = resultCounter.decrementAndGet();\r
- if (count == 0) {\r
- if (onceGuard.compareAndSet(false, true)) {\r
- procedure.execute(graph, result);\r
- }\r
- } else if (count < 0) {\r
- System.out.println(this + ": execute invoked more than expected (count=" + count + ", procedure=" + procedure + ")");\r
- }\r
- }\r
-\r
-}\r
+/*******************************************************************************
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management
+ * in Industry THTH ry.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ * VTT Technical Research Centre of Finland - initial API and implementation
+ *******************************************************************************/
+package org.simantics.db.common.procedure.guarded;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.simantics.db.AsyncReadGraph;
+import org.simantics.db.common.procedure.adapter.AsyncProcedureAdapter;
+import org.simantics.db.procedure.AsyncProcedure;
+import org.simantics.db.procedure.Procedure;
+
+/**
+ * An asynchronous database callback procedure that is guarded against multiple
+ * invocations to {@link Procedure#execute(Object)} and
+ * {@link Procedure#exception(Throwable)}. Only the first invocation of is
+ * delegated or the Nth invocation to {@link Procedure#execute(Object)} where
+ * Nth is <code>expectedResults</code>.
+ *
+ * @author Tuukka Lehtonen
+ *
+ * @param <T>
+ */
+public class GuardedAsyncProcedureWrapper<T> extends AsyncProcedureAdapter<T> {
+
+ private final AsyncProcedure<T> procedure;
+ private final AtomicBoolean onceGuard = new AtomicBoolean(false);
+ private final AtomicInteger resultCounter;
+
+ public GuardedAsyncProcedureWrapper(AsyncProcedure<T> procedure, int expectedResults) {
+ this.procedure = procedure;
+ this.resultCounter = new AtomicInteger(expectedResults);
+ }
+
+ @Override
+ public void exception(AsyncReadGraph graph, Throwable t) {
+ if (onceGuard.compareAndSet(false, true)) {
+ procedure.exception(graph, t);
+ }
+ }
+
+ @Override
+ public void execute(AsyncReadGraph graph, T result) {
+ int count = resultCounter.decrementAndGet();
+ if (count == 0) {
+ if (onceGuard.compareAndSet(false, true)) {
+ procedure.execute(graph, result);
+ }
+ } else if (count < 0) {
+ System.out.println(this + ": execute invoked more than expected (count=" + count + ", procedure=" + procedure + ")");
+ }
+ }
+
+}